To develop an whitening cosmetics, we isolated the melanogenesis inhibitors from the unripe fruits of Poncirus trifoliata (Rutaceae). Isolated compounds were identified as poncirin(l), naringin(2), bis(2-methylheptyl)phthalate(3), avenalumic acid methyl ester(4) by comparison of physical and spectral data with those reported in the literature. Among the isolated compounds, bis(2-methylheptyl)phthalate showed most potent inhibitory effect on the melanogenesis in cultured B-16 mouse melanoma cell lines$(IC_{50},\;36.8\;{\mu}M)$ compared with kojic acid$(IC_{50},\;150\;{\mu}M)$.

Twenty eight compounds were isolated from the whole plant of Euphorbia jolkinii and evaluated for inhibitory effect on $5{\alpha}-reductase$ activity. Among the tested compounds, 1-desgalloyl eugeniin, hippomanin A, euphorbin D, exocoecarianin, rugosin E, and pentagalloyl glucose showed potent inhibitory effect on the enzyme activity. The inhibitory potency of rugosin E and euphorbin D, which are dimeric ellagitannins on $5{\alpha}-reductase$ activity, was 7-to 8-fold stronger than that of ${\gamma}-linolenic$ acid.

We previously reported that the exogenous administration of cumambrin A, a sesquiterpene lactone from the dried flowers of Chrysanthemum boreale Makino has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In the present study, we further investigated the effect of cumambrin A on the relaxation of phenylephrine-induced precontracted rat aortic artery rings. The potency of cumambrin A was than compared to verapamil, a well known $Ca^{2+}-channel$ blocker. The results demonstrate that the isolated rat aortic arteries are relaxed to basal tension at a concentration of $5{\times}10^{-5}\;M$ cumambrin A treatment. The results also show that the phenylephrine-induced contraction is inhibited by a pretreatment of cumambrin A. Co-treatment of cumambrin A and verapamil showed a strong synergetic effect on the relaxation of rat aortic artery rings. Thus, these data demonstrate that cumambrin A is a potent relaxant of rat aortic smooth muscle and suggest that cumambrin A modulates intracellular or extracellular $Ca^{2+}$ mobilization.

The Chinese crude drug, 'Man Sam(蔓蔘)', which is derived from the root of Codonopsis plants of the family Campanulaceae, has been used as a tonic. In China, the same crude drug derived from Codonopsis plants, called 'Dang Same(?蔘)', has been used as remedies for anorexia, fatigue, cough, etc. Although Codonopsis roots have been widely used for medicinal purposes in Korea, the botanical origin of the crude drug has never been studied pharmcognostically. To clarify the botanical origin of 'Man Sam', the root morphology and anatomy were examined for the Korean species of Codonopsis species, such as C. lanceolata (Sieb. et Zucc.) Trautv., C. pilosula (Franch.) Nannf. and C. ussuriensis (Rupr. et Maxim.) Hemsl. The study shows that 'Man Sam' is the root of Codonopsis pilosula.

Korean folk medicine 'Da Rae Ip' has been used to cure intestinal catarrh, stomach cancer and acute gastritis. The botanical origin of the crude drug has never been studied pharmacognostically. To clarify the botanical origin of 'Da Rae Ip', the morphological and anatomical characteristics of the leaves of Actinidia species growing in Korea and Japan; i.e. A. arguta, A. arguta var. rufinervis, A. kolomikta, A. polygama, A. rufa were studied. As a result, it was clarified that 'Da Rae Ip' was the leaf of Actinidia arguta and Actinidia polygama.

Reactive oxygen species (ROS) are known to cause oxidative modification of DNA, proteins, lipids and small cellular molecules and are associated with tissue damage and are the contributing factors for inflammation, aging, cancer, arteriosclerosis, hypertension and diabetes. We screened the anti-oxidants in V79-4 hamster lung fibroblast cells induced by hydrogen peroxide with eighteen pure compounds isolated from natural products. Allantoin, brassicasterol, and hypaconitine were found to strongly scavenge intracellular reactive oxygen species, which is measured by dichlorodihydrofluorescin diacetate method (DCHF-DA), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical.

This study was undertaken to evaluate the gastrotherapeutic effects of the extract of Rosa rugosa. It can be regarded that the antigastric and anti-ulcerative effect of Rosa rugosa is originated from the reduction of total acid output identified by gastric secretion test. To clarify the protective mechanism of the Rosa rugosa extract, the gastropathy was induced in rats with alcohol-salicylate and the activities of the free radical scavenging enzymes were examined. The acitivity of superoxide dismutase and glutathione peroxide were significantly increased and the total content of glutathione was recovered. We concluded that the protective effect of the extract of Rosa rugosa on gastropathy in rats is its ability increased the activities of the free radical scavenging enzymes.

The protective effects of the DWP-04 [DDB : selenium yeast: glutathione {31.1 : 6.8 : 62.1 (%, w/w)} against hepatotoxicity by carbon tetrachloride $(CCl_4)$ were studied in rats. The rats were intraperitoneally injected with $CCl_4$ (50% in com oil) at initial dose of 1 ml/kg followed by 0.5 ml/kg 3 times during 1 week. The DWP-04 (50, 100 or 200 mg/kg) or its vehicle was administered everyday before the start of $CCl_4$ injection for two weeks. $CCl_4$ induced hepatocelluar degeneration and necrosis, which led to a great increase in serum aminotransferase, alkaline phosphatase activity and serum lipid levels. It was found by biochemical analysis that $CCl_4$ treatment remarkably increased thiobarbituric acid reactive substances and physphatidylcholine hydroperoxide in hepatic tissues and induced antioxidant enzymes such as catalase and superoxide dismutase (SOD). Liver and serum lipids were significantly lower in rats fed on DWP-04 than in rats induced by $CCl_4$ only-treatment. These results suggested that the DWP-04 could be a promising candidate for the protection of liver injury based on the preventive effects against lipid peroxidation and serum biochemical parameters.

Reactive oxygen species (ROS) are continuously produced at a high rate as a by-product obtained in the aerobic metabolism. A major portion of living organisms has defense system as superoxide dismutase or catalase against damage produced by ROS. Several lines of evidence provided that ROS appears to cause to develop aging and various diseases. Spatholobus suberectus Dunn has been known as a Korean folk medicine for promoting blood circulation and relieving blood stasis as anemia. In this study, we have investigated the antioxidant activities of Spatholobus suberectus Dunn in order to find the antioxidant substances from natural products. For various antioxidant experiment, the major antioxidant component was isolated from EtOAc extract of Spatholobus suberectus Dunn. This compound was identified as (-)-epicatechin by chemical and physical analysis.

Urease plays an important role in the urea metabolism and the effect of urease activity on human and environment is enormous. For instance, urease acts as a virulence factor of the urinary and gastrointestinal tracts infections in human and animal, being involved in kidney stone formation, catheter encrusatation, pyelonephritis, ammonia encephalopathy, hepatic coma, and urinary tract infections. Widespread urease activity in soil induces a plant damage due to ammonia toxicity and pH increase. Therefore, urease activity regulation through urease inhibitors would lead to an enhanced efficiency of urea nitrogen uptake in plants and to the improved therapeutic strategies for ureolytic bacterial infections. To search for new inhibitory compounds on urease activity from herbs, MeOH extracts of herbs were screened. Among of them, the MeOH extracts of Areca catechu exhibited an excellent inhibitory effect on urease activity. Two compounds were isolated from the ethyl acetate fraction by the activity guided fractionation. Their chemical structures were identified as (+)-catechin(compound I) and allantoin(compound II) by spectroscopic evidence, respectively. Compound I showed a stronger inhibitory effect on urease activity than compound II.

One sesquiterpenoid was isolated from the methanol extract of Atractylodes rhizomes which has been used as traditional medicine for diuresis and the compound was established as selina-4(14),7(11)-dien-8-one by the spectroscopic methods. The compound$(IC_{50}<10\;ppm)$ has inhibitory effects on melanogenesis in B16 mouse melanoma.